Vehicles with dual air brake systems:

Question

Before driving a vehicle with a dual air brake system, you must allow the air compressor time to build up at least 100 psi of air pressure in both the primary and secondary systems.

Accepted Answer

Must be run to build enough air pressure to brakes to operate properly.

Answer

Maintain full-capacity air pressure in the braking systems even when the vehicle is not running.

Answer

Maintain some air pressure in the braking systems when the vehicle is not running.

Answer

Do not need time to build air pressure before a trip.